CCR1009-7G-1C-1S+ combi port incompatibility with UBNT FiberPoe

I try to connect the combiport on CCR1009-7G-1C-1S+ with S-31DLC20D fiber module to UBNT FiberPoe Converter with S-31DLC20D.
Link doesn’t go up.
Exactly same setup on CCR 1009-8G-1S-1S+ with S-31DLC20D fiber module to UBNT FiberPoe Converter with S-31DLC20D works.
Connecting both routers CCR 1009-8G-1S-1S+ with S-31DLC20D to CCR1009-7G-1C-1S+ with S-31DLC20D works.

CCR1009-7G-1C-1S+ :
combi1.jpg
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combi2.jpg
I sent supout to support@ and i post the problem here in the hope to be usefull to anyone who gets trouble with same setup.

are you running the same firmware version on both. Have you updated the airfibre firmware.

RouterOs6.38.5 and AirOs AF3.2.1. But i tried also with laptop and router connected to FiberPoe ethernet port, without success

Are you connecting any Ethernet cables at same time as combo. Remember the combo is linked to Ethernet port so you can use 1 or other